This invention concerns a monitoring system for hydro turbines and more specifically a system for start and stop of such turbines and adjustment of the vane angles in one or several turbines.
The hydro turbine comprises a rotating hub provided with a number of vanes and arranged in a tube or the like for flowing water. The rotary energy obtained is transmitted to a generator for producing electric current.
The rotary energy generated is of course entirely dependent on the amount of flowing water as well as its potential energy, i.e. pressure head. The water amount may vay considerably which means that the turbine will operate with different volume flows at different times. As the turbine is designed to have a maximum efficiency at a certain flow and a certain pressure head, the energy of the water will be utilized to a greater or lesser extent.
By designing the vanes to be adjustable, which means that the vane angle with relation to the water flow may be varied, there is a possibility of optimizing the efficiency within a relatively wide range of water amounts.
An additional way to effectively utilize the water in a current is to minimize the amount of water which passes the turbine or turbines without actuating them. One solution is to arrange a number of small turbines in the plant letting many or few of them operate in dependence on the available amount of water.